Head Impulse Test

What is the Head Impulse Test?

The Head Impulse Test, also known as the head thrust test, is a clinical examination used for detecting vestibular hypofunction and assessing the function of the semicircular canals in the inner ear. It is a crucial diagnostic tool for identifying vestibular dysfunction, particularly in patients with dizziness, vertigo, or balance disorders.

This test is typically administered to patients experiencing unsteady gait, unexplained falls, or acute vestibular syndrome. The primary goal is to evaluate the patient's head and eye velocity responses to sudden head movement, providing insights into their vestibular function.

Advantages and limitations of the test

The test is simple and can be performed at the bedside without specialized equipment. Moreover, the examiner can instantly observe and interpret the patient's response, making it a great tool for screening. It also has high clinical value because of its moderate sensitivity (63%) and high specificity (93%).

However, the test primarily assesses high-frequency vestibular function and may not detect low-frequency abnormalities. The accuracy of the test can depend on the examiner's skill and experience. Additionally, high acceleration head rotations required during the test may pose a risk of injury or exacerbate existing neck issues.

How to perform the Head Impulse Test

Performing the Head Impulse Test involves several key steps to ensure accurate results and patient safety. Here’s the procedure for the normal Head Impulse Test:

1. Verify that the patient does not have any neck issues like vertebrobasilar insufficiency and has an adequate range of neck motion. Otherwise, terminate the test.
2. Seat the patient comfortably with their head in a neutral position.
3. Inform the patient about the procedure to ensure cooperation and reduce anxiety.
4. Firmly hold the patient's head with both hands.
5. Instruct the patient to fixate on a stationary target, such as your nose.
6. Rotate the patient's head to the side being tested and back to the center by 10-15 degrees.
7. Observe the patient's eye movements during and after the head rotation.
8. Repeat on the other side and observe.

Results and interpretation of the Head Impulse Test

Understanding the results of the Head Impulse Test is crucial for accurately diagnosing vestibular disorders. The test evaluates the vestibulo-ocular reflex (VOR), and the presence or absence of corrective saccades serves as a key clinical sign of vestibular function.

Positive test

Corrective saccades indicate a positive test. This typically signifies a vestibular hypofunction on the side to which the head was rotated, also known as a unilateral vestibular deficit. Further diagnostic tests like the video Head Impulse Test (vHIT), active Head Impulse Test, or vestibular evoked myogenic potentials (VEMP) may be recommended in such cases.

Negative  test

The test is negative if no corrective saccades are observed, suggesting normal semicircular canal function. However, additional tests may still be warranted if the patient exhibits persistent symptoms.

Next steps

Depending on the test results and observed symptoms, the next steps may include:

• Referral to a specialist for further evaluation
• Vestibular rehabilitation therapy
• Additional imaging studies or audiometric tests

Benefits of using our template

Our Head Impulse Test template offers a multitude of benefits designed to enhance the efficiency and accuracy of your vestibular assessments:

Structured process

The template ensures a systematic approach to performing the bedside Head Impulse Test. This structured methodology helps reduce the likelihood of errors and inconsistencies, leading to more reliable results.

Detailed instructions

Our template provides clear, step-by-step guidance to support healthcare professionals in executing the test precisely. This includes instructions on assessing peak head velocity and peak head acceleration, which are crucial for accurate diagnosis.

Comprehensive documentation

Our template facilitates the accurate recording of test results and observations. Capturing details such as head position, head impulses, and head rotation aids in creating thorough patient records  essential for ongoing clinical evaluation.

Effective training tool

For training new staff or students, our template helps teach vestibular assessment techniques. It provides a practical framework for understanding and identifying clinical signs of vestibular dysfunction.

Our template streamlines the head impulse testing process, improves diagnostic accuracy, and enhances patient care. By adopting this tool, you can ensure a high standard of clinical practice and support continuous learning within your team.